Circuit, base station, method and recording medium

Abstract

Circuit, base station, method and recording medium. [Problem] A mechanism for wireless communication of a device that flies freely in a three-dimensional space is provided. [Solution] A circuit is provided with: an acquisition unit that acquires altitude information indicating a measurement result of an altitude; and a measurement report control unit that controls measurement report processing of reporting to a base station reference signal information indicating a measurement result of a reference signal sent from the base station and a measurement report message of the altitude information based on a relationship between the altitude information acquired by the acquisition unit and altitude region setting information.

Description

[0001] This application is a divisional application of the patent application with application number 201780057725.6, invention name “Circuit, base station, method and recording medium”, and international application date of August 15, 2017, all contents of which are incorporated herein by reference. Technical Field

[0002] The present disclosure relates to a circuit, a base station, a method and a recording medium. Background Art

[0003] In recent years, research and development related to drones have been conducted and are attracting attention. Drones are small unmanned aircraft also known as unmanned aerial vehicles (UAVs). According to an economic report released by the Association for Unmanned Aerial Vehicles International, the market size of drones in the United States alone is estimated to be about 82 billion US dollars in 2025, and it is estimated that 100,000 new jobs will be created. Drones can use airspace that has not been available to any means of land, sea, and air so far to provide goods and information. Therefore, drones are called the industrial revolution in the air and are considered to be an important business field in the future.

[0004] Generally, it is considered that a drone flies while performing wireless communication. Therefore, it is desirable to develop a technology that enables a drone to perform stable wireless communication. For wireless communication used by a device whose position can be changed, many technologies have been developed so far. For example, the following patent document 1 discloses a technology related to handover of a mobile communication terminal on an airplane that passes through the coverage of each base station at high speed.

[0005] Citation List

[0006] Patent Literature

[0007] Patent Document 1: US2016 / 0029370A Summary of the invention

[0008] Technical issues

[0009] However, the wireless communication systems proposed in the above-mentioned patent documents and the like are not designed on the premise of a device such as a drone that can fly freely in a three-dimensional space.

[0010] Thus, the present disclosure provides a structure for wireless communication of a device capable of flying freely in three-dimensional space.

[0011] Solution to the problem

[0012] According to the present disclosure, a circuit is provided, comprising: an acquisition unit, the acquisition unit being configured to acquire altitude information indicating a measurement result of an altitude; and a measurement report control unit, the measurement report control unit being configured to control measurement report processing of reporting to a base station reference signal information indicating a measurement result of a reference signal sent from the base station and a measurement report message of the altitude information based on a relationship between the altitude information acquired by the acquisition unit and altitude area setting information.

[0013] In addition, according to the present disclosure, a base station is provided, comprising: a reference signal sending unit, the reference signal sending unit being configured to send a reference signal; and a notification unit, the notification unit being configured to notify a terminal device of altitude area setting information, the terminal device controlling a report including reference signal information indicating a measurement result of the reference signal and measurement report processing of a measurement report message of the altitude information based on the relationship between the altitude information indicating a measurement result of the altitude and the altitude area setting information.

[0014] In addition, according to the present disclosure, a method is provided, including: obtaining altitude information indicating a measurement result of altitude; and controlling, through a processor, based on the relationship between the acquired altitude information and altitude area setting information, a measurement report processing of reporting to a base station reference signal information indicating a measurement result of a reference signal sent from the base station and a measurement report message of the altitude information.

[0015] In addition, according to the present disclosure, a method is provided, including: sending a reference signal; and notifying a terminal device of altitude area setting information through a processor, wherein the terminal device controls a measurement report processing of a report including reference signal information indicating the measurement result of the reference signal and a measurement report message of the altitude information based on the relationship between the altitude information indicating the measurement result of the altitude and the altitude area setting information.

[0016] In addition, according to the present disclosure, there is provided a recording medium having a program recorded thereon, wherein the program causes a computer to function as follows: an acquisition unit, wherein the acquisition unit is configured to acquire altitude information indicating a measurement result of an altitude; and a measurement report control unit, wherein the measurement report control unit is configured to control measurement report processing of reporting to a base station reference signal information indicating a measurement result of a reference signal sent from the base station and a measurement report message of the altitude information based on a relationship between the altitude information acquired by the acquisition unit and altitude area setting information.

[0017] In addition, according to the present disclosure, there is provided a recording medium having a program recorded thereon, wherein the program enables a computer to function as follows: a reference signal sending unit, wherein the reference signal sending unit is configured to send a reference signal; and a notification unit, wherein the notification unit is configured to notify a terminal device of altitude area setting information, wherein the terminal device controls a measurement report processing of a report including reference signal information indicating a measurement result of the reference signal and a measurement report message of the altitude information based on a relationship between altitude information indicating a measurement result of the altitude and the altitude area setting information.

[0018] Advantageous Effects of the Invention

[0019] According to the present disclosure, as described above, a structure for wireless communication of a device capable of flying freely in a three-dimensional space can be provided. Note that the effects described above are not necessarily restrictive. Together with or in place of the above effects, any effect described in this specification or other effects that can be grasped based on this specification can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is an explanatory diagram illustrating an example of the configuration of the system according to the present embodiment.

[0021] Figure 2 This is an explanatory diagram illustrating an example of legal restrictions on drones.

[0022] Figure 3 This is an explanatory diagram illustrating an example of wireless communication via a drone.

[0023] Figure 4 This is an explanatory diagram illustrating an example of wireless communication via a drone.

[0024] Figure 5 This is an explanatory diagram illustrating an example of wireless communication via a drone.

[0025] Figure 6 This is an explanatory diagram illustrating an example of wireless communication via a drone.

[0026] Figure 7 is a sequence diagram illustrating an example of the flow of a handover process performed in the system according to the present embodiment.

[0027] Figure 8 is a block diagram illustrating an example of a logical configuration of a base station according to the present embodiment.

[0028] Fig. 9 is a block diagram illustrating an example of a logical configuration of a drone according to the present embodiment.

[0029] Fig.10This is a flowchart illustrating an example of the flow of measurement report processing performed by the drone according to this embodiment.

[0030] Fig.11 is a sequence diagram illustrating an example of the flow of measurement report processing performed in the system according to the present embodiment.

[0031] Fig.12 is a block diagram illustrating a first example of a schematic configuration of an eNB.

[0032] Fig.13 is a block diagram illustrating a second example of a schematic configuration of an eNB. DETAILED DESCRIPTION

[0033] The preferred embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. Note that in the specification and the drawings, structural elements having substantially the same function and structure are denoted by the same reference numerals, and repeated description of these structural elements is omitted.

[0034] In addition, in the specification and the drawings, different letters are added after the same reference numerals to distinguish between elements having substantially the same functional configuration. For example, when necessary, multiple elements having substantially the same functional configuration are distinguished into, for example, base stations 100A, 100B, and 100C. Here, in the case where it is not necessary to particularly distinguish between multiple elements having substantially the same functional configuration, only the same reference numerals are given. For example, in the case where it is not necessary to particularly distinguish between base stations 100A, 100B, and 100C, base stations 100A, 100B, and 100C are simply referred to as base stations 100.

[0035] Note that the description will be given in the following order.

[0036] 1. Introduction

[0037] 1.1. Use cases of drones

[0038] 1.2. Wireless communication via drone

[0039] 1.3. General issues related to drones

[0040] 1.4. System Configuration Example

[0041] 1.5. Regulations

[0042] 1.6.Handover

[0043] 2. Configuration examples for each device

[0044] 2.1. Base station configuration example

[0045] 2.2. UAV configuration example

[0046] 3. Technical features

[0047] 4. Application examples

[0048] 5. Conclusion

[0049] <<1. Introduction>>

[0050] <1.1. Use cases of drones>

[0051] Consider various use cases of drones. Below, examples of representative use cases are described.

[0052] -entertainment

[0053] For example, consider a use case in which a bird's-eye view photo, a moving image, etc. are taken by mounting a camera on a drone. In recent years, it has become easy to shoot at angles that were previously difficult to shoot from the ground, such as dynamic shooting of sports, etc.

[0054] -transportation

[0055] For example, consider a use case where luggage is transported using drones. There is already a movement to start service introduction.

[0056] - Public safety

[0057] For example, consider use cases such as surveillance and prisoner tracking. Previously, there has also been a move to start service introduction.

[0058] -intelligence

[0059] For example, consider a use case where drones are utilized to provide information. Research and development has been conducted on drone base stations that act as drones that operate as base stations. By providing wireless services from the air, drone base stations can provide wireless services to areas where it is difficult to establish Internet circuits.

[0060] -Sensing

[0061] For example, consider the use case of utilizing drones for surveying. Since surveys that were previously conducted by humans can now also be conducted en masse by drones, efficient surveying can be performed.

[0062] -Laborers

[0063] For example, consider a use case where drones are used as a workforce. For example, drones are expected to be used in various fields of agriculture for spraying pesticides or pollination.

[0064] -maintain

[0065] For example, consider a use case where drones are used for maintenance. By using drones, maintenance can be performed in places that are difficult for humans to check (such as under a bridge).

[0066] <1.2. Wireless communication via drone>

[0067] The above discusses the use of drones in various situations. In order to realize such use cases, various technical requirements are imposed on drones. Among the technical requirements, communication can be listed as an important requirement in particular. Since drones fly freely in three-dimensional space, it is not realistic to use wired communication and wireless communication is envisioned. Note that as uses of wireless communication, control of drones (i.e., remote control), provision of information from drones, etc. are considered.

[0068] In some cases, communication through drones is also referred to as drone-to-X (D2X). The communication partners of the drone in D2X communication are considered to be, for example, another drone, a cellular base station, a Wi-Fi (registered trademark) access point, a television (TV) tower, a satellite, a road side unit (RSU), and a human (or a device carried by a human), etc. The drone can be remotely controlled via device-to-device (D2D) communication with a device carried by a human. In addition, the drone can also be connected to a cellular system or Wi-Fi for communication. In order to further expand the coverage, the drone can be connected to a network in which a broadcast system such as TV is utilized or a network in which satellite communication is utilized for communication. In this way, it is considered that various communication links are formed in the drone.

[0069] <1.3. General issues related to drones>

[0070] Generally, in cellular communications, in order for the base station device and the terminal device to effectively perform wireless communications, the base station device preferably effectively controls radio resources. Therefore, in the prior art LTE and the like, the terminal device reports (i.e., feeds back) measurement information of the transmission path with the base station device and / or terminal device status information to the base station device. Subsequently, the base station device controls the radio resources based on the information reported from the terminal device.

[0071] However, the structure for feedback control performed in cellular communications in the past was designed under the premise of using terminal devices on the ground or in buildings, that is, using terminal devices in two-dimensional space. In other words, the structure for feedback control performed in cellular communications in the past may be considered unsuitable for drones that fly freely in three-dimensional space. Therefore, it is desirable to expand the structure of cellular communications for drones.

[0072] <1.4. System Configuration Example>

[0073] The following will refer to Figure 1 , illustrating an example of the configuration of the system according to the present embodiment.

[0074] Figure 11 is an explanatory diagram illustrating an example of the configuration of a system according to the present embodiment. Figure 1 As shown in the diagram, the system 1 according to this embodiment includes a base station 100, a terminal device 200 and a terminal device 300.

[0075] The base station 100A is a macrocell base station that operates a macrocell 11A. The macrocell base station 100A is connected to a core network 12. The core network 12 is connected to a packet data network (PDN) 13 via a gateway device (not shown). The macrocell 11A may be operated in accordance with any wireless communication scheme, such as long term evolution (LTE), LTE-advanced (LTE-A), and 5G. Note that 5G is assumed to include new radio (NR), new radio access technology (NRAT), and further evolved universal terrestrial radio access (FEUTRA).

[0076] The base stations 100B and 100C are small cell base stations that respectively operate the small cells 11B and 11C. The small cell base stations 100B and 100C are connected to the macro cell base station 100A. The small cells 11B and 11C may be operated according to any wireless communication scheme, such as LTE, LTE-A, and 5G.

[0077] The terminal devices 200 and 300 are devices that perform wireless communication by connecting to a cell operated by the base station 100. Figure 1 As shown in the diagram, the terminal device 200 is a drone that flies freely in a three-dimensional space. In addition, the terminal device 300 is a device such as a smart phone that is assumed to move on a two-dimensional plane. In the following description, in order to distinguish between the terminal device 200 and the terminal device 300, the terminal device 200 will also be referred to as the drone 200. By performing cellular communication, the drone 200 can send and receive data in real time in a wide coverage area provided by, for example, cellular communication, and receive control for autonomous flight. Figure 1 In the example shown in the diagram, the drone 200A and the terminal device 300A are connected to the macro cell 11A provided by the macro cell base station 100A, and the drone 200B and the terminal device 300B are connected to the small cell 11B provided by the small cell base station 100B.

[0078] Note that in the following description, in the case where there is no particular need to distinguish between the macro cell base station 100 and the small cell base station 100 , they are collectively referred to as the base station 100 .

[0079] <1.5. Regulations>

[0080] Assume that regulations corresponding to the altitude at which drones are flown are imposed.

[0081] The drone can stably and autonomously fly by using advanced information processing of information input from multiple sensors such as a global navigation satellite system (GNSS), a gyro sensor, and an imaging element. Therefore, for a predetermined flight plan from a departure point to a destination, the drone can achieve highly automated flight or flight with effective remote control. The drone may have various forms corresponding to various applications. For example, in the case where the drone is a helicopter-type drone, the drone has various flight modes.

[0082] Unlike existing terminal devices such as smartphones used by people, drones have the characteristic of extremely high freedom of existence relative to height (e.g., height from the ground). In addition, drones have the characteristic of having extremely high moving speed in the vertical direction. For example, it is considered that although the drone exists on the ground at a certain moment, after the flight starts, the drone will reach a height of tens of meters in the air after only a few seconds of rapid climbing. In addition, it is also considered that after climbing, the flight of the drone terminal is switched to horizontal flight, and after tens of seconds, the drone reaches a location hundreds of meters away, and then lowers its altitude to return to the ground height of the remote location.

[0083] In the future, in order to ensure safety, it is likely that certain legal restrictions will be imposed on drones whose position relative to altitude changes at extremely high speeds and in a variety of ways. Currently, various legal restrictions are being proposed by government agencies and private companies. Figure 2 Illustrate examples of possible legal restrictions.

[0084] Figure 2 This is an explanatory diagram illustrating an example of legal restrictions on drones. Figure 2 The X-axis direction in means the horizontal direction, and the Z-axis direction means the height direction. Figure 2 As shown in the diagram, it is considered that the airspace can be divided into multiple airspaces, and for each divided airspace, legal restrictions are imposed. For example, the airspace can be divided according to the type and / or height of the buildings on the ground. Airspace 21 is the airspace up to altitude z1, and for example, low-speed flight is allowed. Airspace 22 is the airspace from altitude z1 to altitude z2, and for example, high-speed flight is allowed. Airspace 23 is the airspace from altitude z2 to altitude z3, which is the airspace over areas with high safety requirements such as densely populated areas and airports, and for example, flight itself is prohibited. Airspace 24 is an airspace higher than altitude z3, and for example, the flight of authorized drones is allowed.

[0085] The users of drones are required to stably and efficiently manage the flight of drones while complying with such legal restrictions. In addition, cellular service providers are required to provide a stable and efficient communication environment for drones even if the number of drones performing cellular communications increases in the future. In addition, cellular service providers are required to prevent degradation of service quality for terminal devices other than drones.

[0086] <1.6. Handover>

[0087] Figure 3 It is an explanatory diagram illustrating an example of wireless communication by the drone 200. Figure 3 Viewed from the horizontal direction Figure 1 In the example of the view of the macro cell 11A illustrated in FIG, the X-axis direction means the horizontal direction, and the Z-axis direction means the height direction. Since the drone 200A can move at high speed and over a wide area, the drone 200 can stably communicate by connecting to the wide macro cell 11A provided by the macro cell base station 100A. In this way, for the drone 200, compared with a communication method such as Wi-Fi in which the communication distance is short, a cellular in which the communication distance is long is more desirable, and in particular, connection with a macro cell with excellent coverage is desirable.

[0088] However, it is assumed that communication through the drone 200 is accompanied by a large amount of data communication, such as flight control data and image information taken by the drone 200. Therefore, it is not desirable for the drone 200 to always connect to the macro cell for communication. In order to improve the frequency utilization efficiency of the network, avoid congestion, etc., if possible, it is desirable to convert the communication into communication by connecting to a small cell. By properly utilizing small cells by operators, stable data communication can be provided at a low altitude and at a high speed while suppressing the consumption of the more expensive resources of the macro cell. Switching between macro cells and small cells will refer to Figure 4 illustrate.

[0089] Figure 4 It is an explanatory diagram illustrating an example of wireless communication by the drone 200. Figure 4 Viewed from the horizontal direction Figure 1 In the example of the view of the macro cell 11A and the small cell 11B illustrated in FIG. 1 , the X-axis direction means the horizontal direction, and the Z-axis direction means the height direction. Figure 4As shown in the diagram, in the case where the drone 200B is located near the ground (i.e., flying near the ground), it is desirable that the drone 200B connects to the small cell 11B provided by the small cell base station 100B. Meanwhile, in the case where the drone 200B is located at a higher altitude, it is desirable that the drone 200B connects to the macro cell 11A provided by the macro cell base station 100A. By switching the connection destination in this way, it is possible to achieve an enhancement in the ability of the small cell to accommodate terminals and stability provided by the wide area connection of the macro cell.

[0090] In this way, in terms of effective use of radio resources and flight stability of the drone 200, it is ideal to perform handover associated with the climb and descent of the drone 200.

[0091] Here, as described above, it is assumed that regulations regarding the flight altitude may be imposed on the drone 200. Subsequently, it is assumed that the drone 200 is used with a flight plan pre-programmed with rules according to the determined flight altitude based on the regulations. For example, it is assumed that the drone 200 continues to climb after taking off from the ground, and when reaching a predetermined altitude area (e.g., the high-speed flight altitude area 31), it starts high-speed horizontal flight.

[0092] In this regard, in cellular communications of the related art, the timing of handover is defined based on the received signal strength of a reference signal transmitted from a base station. In the case where the drone 200 performs handover based on the received signal strength in a similar manner, a gap may occur between the timing of handover based on the received signal strength and the boundary of the flight altitude defined by regulations. This will be referred to in Figure 5 and Figure 6 Detailed description.

[0093] Figure 5 It is an explanatory diagram illustrating an example of wireless communication by the drone 200. Figure 5 Viewed from the horizontal direction Figure 1 In the example of the view of the macro cell 11A and the small cell 11B shown in the diagram, the X-axis direction means the horizontal direction, and the Z-axis direction means the height direction. Figure 5As shown in the diagram, there may be a situation where the upper limit of the small cell 11B whose boundary is defined by power does not intersect with the lower limit of the high-speed flight altitude area 31. In this case, the drone 200 is handed over to the macro cell 11A at the upper end of the small cell 11B (for example, the position indicated by the reference numeral 32). Subsequently, if the drone 200 reaches the high-speed flight altitude area 31, the drone 200 starts high-speed flight while maintaining the connection with the macro cell 11A. In this case, the connection of the drone 200 is converted into a connection with the macro cell 11A before starting the high-speed flight. That is, since the drone 200 starts moving at high speed after ensuring a wide connection coverage in advance, no special problems will occur. Note that the high-speed flight high-speed band 31 may correspond to the above reference numeral 32. Figure 2 Description of airspace 22.

[0094] Figure 6 This is an explanatory diagram illustrating an example of wireless communication using the drone 200. Figure 6 Viewed from the horizontal direction Figure 1 In the example of the view of the macro cell 11A and the small cell 11B shown in the diagram, the X-axis direction means the horizontal direction, and the Z-axis direction means the height direction. Figure 6 As shown in the diagram, there may be a situation where the upper limit of the small cell 11B whose boundary is defined by power intersects with the lower limit of the high-speed flight altitude area 31. In this case, there is a possibility that the drone 200 starts high-speed flight while maintaining the connection with the small cell 11B. In this case, the drone 200 attempts to handover to the macro cell 11A at the upper end of the small cell 11B (for example, the position indicated by the reference numeral 32). In addition, there may be a situation where the drone 200 crosses the small cell in a short time. In such a case, there is a possibility that the drone 200 exceeds the cell range of the small cell in a short time.

[0095] The cell radius of the small cell may be set to be sufficiently small according to regulations for the drone 200. However, in this case, it is not appropriate to impose strict restrictions on the cell radius of the small cell. In addition, it is not realistic to identify and manage the size of the cell radius in the air.

[0096] like Figure 6 As in the example shown in the diagram, if the drone 200 flies out of the cell range of the small cell in a short time, there is a possibility that the handover may fail due to the influence of the time delay from measurement to execution of the handover. To explain this, first refer to Figure 7 Describe the handover process.

[0097] Figure 71 is a sequence diagram illustrating an example of the flow of a handover process performed in the system 1 according to the present embodiment. The present sequence involves the drone 200, the small cell base station 100B, the macro cell base station 100A, and the mobility management entity (MME) 12. In addition, it is assumed that the drone 200 is connected to the small cell base station 100B in advance.

[0098] like Figure 7 As shown in the diagram, first, the small cell base station 100B sends a measurement configuration message to the drone 200 (step S102). The measurement configuration message can be sent as, for example, a radio resource control (RRC) connection reconfiguration message. The drone 200 measures the reference signals sent from the surrounding base stations based on the measurement configuration message and system information (step S104). Subsequently, when a predetermined condition is met, the drone 200 sends a measurement report message including information indicating the measurement result to the small cell base station 100B (step S106).

[0099] Subsequently, the small cell base station 100B determines the handover based on the received measurement report message (step S108). In the case of determining to perform handover, the small cell base station 100B sends a handover request message to the target base station (here, the macro cell base station 100A) (step S110). Subsequently, in response to the received handover request message, the macro cell base station 100A sends an ACK signal to the small cell base station 100B (step S112). Subsequently, after receiving the ACK signal, the small cell base station 100B sends an RRC connection reconfiguration message to the drone 200 to indicate the movement of the cell (step S114).

[0100] Subsequently, the drone 200 performs a process of detaching from the small cell to which the drone 200 is connected (step S116), and establishes synchronization with the macro cell base station 100A (step S118). Subsequently, the macro cell base station 100A sends a path switching request to the MME 12 (step S120), and receives an ACK signal (step S122). Subsequently, the small cell base station 100B transmits a packet data convergence protocol (PDCP) packet data unit (PDU) to the macro cell base station 100A. In addition, the drone 200 sends an RRC connection reconfiguration completion message to the macro cell base station 100A (step S126).

[0101] Referring to the flow described above, in the handover process, there is a time delay from the drone 200 performing measurement to determining the handover and receiving the RRC connection reconfiguration message. Therefore, there is a possibility that the drone 200 connected to the small cell exceeds the cell range of the small cell in a short time due to suddenly starting to fly at a high speed when the drone 200 reaches a certain height, thereby failing to receive the RRC connection reconfiguration message. As a result, the drone does not perform handover, and as a result, the connection with the small cell base station 100 to which the drone 200 has been connected is interrupted.

[0102] As such, there is a possibility that the drone 200 may fail in handoff and lose connection due to the gap between the timing of handoff based on received signal strength and the boundary of the flight altitude defined by regulations.

[0103] Regarding the situation described above, as one of the prior arts that envisions communication between a mobile body that moves in a three-dimensional manner and a ground station, there is the above-mentioned patent document 1. The above-mentioned patent document 1 discloses a technology that enables a terminal on an aircraft to perform inter-zone handover based on the three-dimensional position information of the aircraft. However, the above-mentioned patent document 1 does not study the regulations regarding flight altitude that may be imposed. Therefore, the above-mentioned patent document 1 does not study the above-mentioned gap between the timing of inter-zone handover based on the received signal strength and the boundary of the flight altitude defined by the regulations. However, it is effective for the terminal to perform measurements in advance to achieve an ideal inter-zone handover, and the above-mentioned patent document 1 does not conduct any research on this point. In addition, however, it is effective for the terminal to perform measurements in advance to achieve an ideal inter-zone handover, and the above-mentioned patent document 1 does not study this point.

[0104] Therefore, in view of the above situation, the present embodiment proposes a structure for wireless communication of a drone 200 that flies freely in a three-dimensional space, and more specifically, a structure for measurement reporting to implement appropriate handover.

[0105] <<2. Configuration examples of each device>>

[0106] <2.1. Base station configuration example>

[0107] Figure 8 1 is a block diagram illustrating an example of the logical configuration of the base station 100 according to the present embodiment. Figure 8 As shown in the diagram, the base station 100 includes an antenna unit 110 , a wireless communication unit 120 , a network communication unit 130 , a storage unit 140 and a processing unit 150 .

[0108] (1) Antenna unit 110

[0109] The antenna unit 110 transmits the signal output from the wireless communication unit 120 as radio waves to the space. In addition, the antenna unit 110 converts the radio waves in the space into signals and outputs the signals to the wireless communication unit 120.

[0110] (2) Wireless communication unit 120

[0111] The wireless communication unit 120 transmits and receives signals. For example, the wireless communication unit 120 transmits a downlink signal to a terminal device and receives an uplink signal from a terminal device.

[0112] (3) Network communication unit 130

[0113] The network communication unit 130 sends and receives information. For example, the network communication unit 130 sends information to other nodes and receives information from other nodes. For example, the other nodes include other base stations and core network nodes.

[0114] (4) Storage unit 140

[0115] The storage unit 140 temporarily or permanently stores programs and various data for operations of the base station 100 .

[0116] (5) Processing unit 150

[0117] The processing unit 150 provides various functions of the base station 100. The base station 100 operates based on the control of the processing unit 150. The processing unit 150 includes a reference signal transmission unit 151, a notification unit 153, and a handover control unit 155. Note that the processing unit 150 may also include constituent elements other than these constituent elements. That is, the processing unit 150 is capable of performing operations other than the operations of these constituent elements. The functions of the reference signal transmission unit 151, the notification unit 153, and the handover control unit 155 will be described in detail later.

[0118] <2.2. Drone Configuration Example>

[0119] Fig. 9 2 is a block diagram illustrating an example of a logical configuration of the drone 200 according to the present embodiment. Fig. 9 As shown in the diagram, the drone 200 according to this embodiment includes an antenna unit 210 , a wireless communication unit 220 , a storage unit 230 , a flight device 240 and a processing unit 250 .

[0120] (1) Antenna unit 210

[0121] The antenna unit 210 transmits the signal outputted from the wireless communication unit 220 as radio waves to the space. Also, the antenna unit 210 converts the radio waves in the space into signals and outputs the signals to the wireless communication unit 220.

[0122] (2) Wireless communication unit 220

[0123] The wireless communication unit 220 transmits and receives signals. For example, the wireless communication unit 220 receives a downlink signal from a base station and an uplink signal transmitted to the base station.

[0124] (3) Storage unit 230

[0125] The storage unit 230 temporarily or permanently stores programs and various data for operations of the terminal device 200 .

[0126] (4) Flight equipment 240

[0127] The flying device 240 is a device having a flying capability, that is, capable of flying. The flying device 240 includes a driving unit 241 , a battery unit 242 , a sensor unit 243 , and a flight control unit 244 .

[0128] The drive unit 241 drives the drone 200 to fly. The drive unit 241 includes, for example, a motor, a propeller, a transmission mechanism for transmitting the power of the motor to the propeller, etc. The battery unit 242 supplies power to each component of the flight device 240. The sensor unit 243 senses various information. For example, the sensor unit 243 includes a gyro sensor, an acceleration sensor, a position information acquisition unit (for example, a signal positioning unit of the global navigation satellite system (GNSS)), an altitude sensor, a battery remaining sensor, a rotation sensor of the motor, etc. The flight control unit 244 controls the drone 200 to fly. For example, the flight control unit 244 controls the drive unit 241 based on the sensor information obtained from the sensor unit 243 so that the drone 200 flies.

[0129] (5) Processing unit 250

[0130] The processing unit 250 provides various functions of the terminal device 200. The processing unit 250 includes an acquisition unit 251 and a measurement report control unit 253. Note that the processing unit 250 may also include constituent elements other than these constituent elements. That is, the processing unit 250 is capable of performing operations other than the operations of these constituent elements. The functions of the acquisition unit 251 and the measurement report control unit 253 will be described in detail later.

[0131] The processing unit 250 is connected to the flight device 240. The processing unit 250 may be implemented as a processor, a circuit, an integrated circuit, or the like.

[0132] <<3. Technical Features>>

[0133] (1) Measurement of reference signal

[0134] The base station 100 (e.g., the reference signal transmission unit 151) transmits a reference signal. The drone 200 (e.g., the measurement report control unit 253) then measures the reference signal transmitted from the base station 100 to obtain reference signal information indicating the measurement result. The reference signal information includes information indicating the signal quality such as reference signal received power (RSRP) and reference signal received quality (RSRQ) of, for example, a primary cell or a neighboring cell. In LTE, in order to perform handover, such measurement processing is also performed in the prior art.

[0135] (2) Height information

[0136] The drone 200 (e.g., the acquisition unit 251) acquires altitude information indicating the measurement result of the altitude. For example, the altitude information can be measured by the sensor unit 243. That is, the drone 200 can acquire the altitude information from the flight device 240. There are various methods for measuring altitude information. For example, the altitude information can be measured by the drone 200 emitting electromagnetic waves such as radio waves, infrared light, and laser to the ground. In addition, the altitude information can be obtained by GNSS. In addition, the altitude information can be estimated from the measurement result of the air pressure based on the relationship between the air pressure and the altitude. In addition, the altitude information can be obtained by receiving radio waves transmitted from a plurality of base stations 100.

[0137] By combining two or more of these measurement methods, the drone 200 can further improve the accuracy of the altitude information. In addition, by correcting the measured altitude information using the correction data transmitted from the base station 100, the drone 200 can further improve the accuracy of the altitude information.

[0138] In addition, the altitude information may be measured by other devices. For example, the altitude information may be measured by another drone 200 flying near the drone 200. In addition, the altitude information may be obtained by receiving radio waves transmitted from the drone 200 by a plurality of base stations 100. In these cases, the drone 200 receives the altitude information from other devices.

[0139] (3) Altitude area setting information

[0140] The base station 100 (for example, the notification unit 153 ) notifies the drone 200 of the altitude zone setting information.

[0141] The altitude zone setting information is information for setting an altitude zone for classifying the state of the altitude of the drone 200. The drone 200 can determine the altitude zone to which the drone 200 belongs based on the relationship between the acquired altitude information and the altitude zone setting information. Note that since the set altitude zone corresponds to the above-mentioned regulations, the altitude zone setting information may differ depending on the country or region.

[0142] The altitude zone setting information includes at least information about an altitude zone in which high-speed flight is possible (e.g., Figure 2 The airspace shown in the diagram 22, Figure 5 or Figure 6 In addition, the altitude area setting information may include information about various altitude areas, such as altitude areas where low-speed flight is possible (e.g., Figure 2 The setting of the airspace 21) shown in the diagram.

[0143] The altitude region setting information includes thresholds for specifying the altitude region, such as the upper altitude limit H1 and the lower altitude limit H2 of the altitude region. Subsequently, the drone 200 determines the relationship between the altitude information and the altitude region setting information based on these thresholds. For example, based on the altitude region setting information about the high-speed flight altitude region, if the altitude of the drone 200 indicated by the altitude information is equal to or greater than H1 and equal to or less than H2, then the drone 200 determines that the altitude falls within the high-speed flight altitude region, otherwise, it is determined that the altitude does not fall within the high-speed flight altitude region.

[0144] The altitude region setting information may further include a value H for providing a margin (ie, an offset) to the threshold value of the designated altitude region. M In the height area, set the information including the margin H M In the case of M When the drone 200 determines the altitude zone to which the drone 200 belongs.

[0145] The drone 200 may determine the relationship between the altitude information and the altitude zone setting information while providing a hysteresis. That is, the drone 200 may provide a hysteresis to the transition of the altitude zone to which the drone belongs. Specifically, in the case where the drone 200 moves to a different altitude zone and flies in the altitude zone after the move for a period of time equal to or greater than a predetermined period, the drone 200 determines that the drone 200 belongs to the altitude zone after the move. In other words, even if the drone 200 moves to a different altitude zone, the drone 200 determines that the drone 200 belongs to the initial altitude zone until the drone 200 flies in the altitude zone after the move for a period of time equal to or greater than a predetermined period. In this way, excessive frequent transitions of altitude zones that may occur due to the drone 200 flying near the boundary of the altitude zone can be suppressed. The altitude zone setting information may include a timer value that provides the above-mentioned predetermined time for the hysteresis. In the case where the altitude zone after the change is maintained for a period of time exceeding the timer value included in the altitude zone setting information, the drone 200 determines that there is a change in the altitude zone.

[0146] There are various notification methods of the altitude area setting information. For example, the base station 100 may notify the altitude area setting information contained in system information (e.g., a master information block (MIB) or a system information block (SIB)). In addition, the base station 100 may notify the altitude area setting information contained in information provided individually for each drone 200, such as a measurement configuration information element (IE) provided in an RRC connection reconfiguration message.

[0147] Furthermore, the altitude zone setting information may include information indicating a value to be set, or may include information indicating a changed value from a current setting.

[0148] Note that the altitude zone setting information may be preset at the drone 200 .

[0149] (4) Measurement report

[0150] The drone 200 (eg, the measurement report control unit 253 ) controls the measurement report process based on the relationship between the acquired altitude information and the altitude region setting information.

[0151] Specifically, the drone 200 uses a parameter corresponding to the relationship between the altitude information and the altitude zone setting information in the measurement report processing. In this way, the drone 200 can recognize or predict the change of the altitude zone in advance and reflect the change in the measurement report processing, so that the drone 200 can perform an appropriate handover associated with the reflection.

[0152] For example, in the case where the altitude area set by the altitude area setting information includes the altitude indicated by the altitude information, the drone 200 controls the measurement report processing by using the parameters corresponding to the altitude area. That is, the drone 200 controls the measurement report processing by using the parameters corresponding to the altitude area to which the drone 200 belongs. In addition, in the case where the difference between the upper limit or lower limit of the altitude area set by the altitude area setting information and the altitude information is within the threshold value, the drone 200 may control the measurement report processing by using the parameters corresponding to the altitude area. For example, even if the drone 200 does not actually belong to the drone 200 in the offset (i.e., the margin H M ), the drone 200 may also use the parameters corresponding to the adjacent height area to control the measurement report processing. In this way, the drone 200 may use the parameters of the height area to which the drone 200 belongs in the near future in advance. In addition, when the drone 200 is within the offset (i.e., the margin H M ), the drone 200 may control the measurement report processing using parameters corresponding to the boundary of the altitude zone where the drone 200 is located. In this way, when the drone 200 flies near the boundary of the altitude zone, the drone 200 may, for example, exceptionally increase the measurement frequency and the report frequency.

[0153] Here, the measurement report process to be controlled may include measurement of a reference signal transmitted from the base station 100, and reporting a measurement report message including reference signal information indicating the measurement result to the base station 100. The report is also performed in the prior art to perform handover. In addition, the measurement report process to be controlled may include measurement of altitude, and reporting a measurement report message including altitude information indicating the measurement result to the base station 100. The measurement report message to be transmitted to the base station 100 may include the reference signal information and the altitude information, or may include one of the reference signal information and the altitude information.

[0154] There are two types of control of the measurement report processing corresponding to the relationship between the altitude information and the altitude region setting information, namely, control of the measurement timing and control of the report timing, which will be described below respectively.

[0155] -Measurement timing

[0156] The drone 200 (e.g., the measurement report control unit 253) may measure the altitude at a timed interval based on a parameter corresponding to the relationship between the altitude information and the altitude zone setting information. For example, the drone 200 measures the altitude at a timed interval based on a parameter corresponding to the altitude zone to which the drone 200 belongs, the adjacent altitude zone to which the drone 200 is close within an offset, or the boundary of the altitude zone (e.g., h-scale to be described later). In this way, for example, the drone 200 may increase the measurement frequency as the altitude increases, or increase the measurement frequency of the altitude near the boundary of the high-speed flight altitude zone, etc., to facilitate the judgment of the handover performed by the base station 100. Note that the measurement accuracy may be improved as the measurement frequency increases.

[0157] The base station 100 notifies the drone 200 of the altitude measurement timing setting information, which includes parameters regarding the measurement timing of the altitude. Subsequently, the drone 200 measures the altitude at a timing based on the altitude measurement timing setting information. The altitude setting timing setting information may be included in the measurement configuration IE provided in the RRC connection reconfiguration message, for example, and notified.

[0158] For example, the altitude measurement timing setting information includes parameters about the measurement mode, such as a measurement period and an offset value of the measurement timing. An example of setting the specific parameters and the measurement timing based on the parameters will be described below. For example, assume that the scaling parameter of the measurement period is h-scale, the parameter of the measurement period is h-period, and the measurement offset parameter is h-offset. In this case, the drone 200 measures the altitude at the timing of the subframe of the system frame number (SFN) calculated using the following equation.

[0159] [Mathematical formula 1]

[0160] SFNmodT=FLOOR(h-offset)(1)

[0161] [Mathematical formula 2]

[0162] subframe = h-offsetmod10(2)

[0163] [Mathematical formula 3]

[0164] T=FLOOR(h-period / h-scale)(3)

[0165] According to the above equation, the measurement timing of the height occurs at a period obtained by scaling h-period using h-scale, and becomes the timing of the SFN where the remainder obtained by dividing the value of the SFN by the period is equal to h-offset. More specifically, the measurement timing of the height becomes the timing of the subframe determined with reference to the value of the last bit of h-offset within the frame period of the above SFN.

[0166] Note that the altitude measurement timing setting information may include the parameter itself to be set, or may include the amount of change from the current setting.

[0167] Furthermore, the reference signal may be measured at a timing corresponding to the measurement timing of the altitude.

[0168] -Report timing

[0169] The drone 200 (e.g., the measurement report control unit 253) may report a measurement report message to the base station 100 at a timing based on a parameter corresponding to the relationship between the altitude information and the altitude zone setting information. For example, the drone 200 reports a measurement report message at a timing based on a parameter corresponding to the altitude zone to which the drone 200 belongs, an adjacent altitude zone to which the drone 200 is close within an offset, or a boundary of an altitude zone (e.g., s-measure to be described later). In this way, for example, the drone 200 may increase the reporting frequency near the boundary of the high-speed flight altitude zone, thereby facilitating the judgment of handover by the base station 100.

[0170] The base station 100 notifies the drone 200 of the report timing setting information including parameters regarding the reporting timing of the altitude information. The drone 200 then reports the altitude information at a timing based on the report timing setting information. For example, the report timing setting information may be included in the measurement configuration IE provided in the RRC connection reconfiguration message and notified.

[0171] Note that the reporting timing in the existing LTE is the timing of occurrence of events A1 to A6, etc., and the parameters regarding events A1 to A6 are provided from the base station as a measurement configuration IE (e.g., ReportConfig). In this embodiment, in addition to these parameters, parameters regarding altitude information are also included in the measurement configuration IE and notified. In addition, new events regarding altitude information can be defined.

[0172] An example of information included in the report timing setting information will be described below.

[0173] For example, the report timing setting information may include information indicating a reporting condition for a measurement report on a reference signal. Specifically, the report timing setting information may include s-measure. s-measure is one of the parameters that define the timing of a measurement report in LTE, and is a threshold value corresponding to the quality (e.g., RSRP) of a reference signal of a primary cell (PCell). In the case where s-measure is included in the report timing setting information, the drone 200 updates the s-measure set at the drone 200. In this way, the drone 200 changes the sending timing of the measurement report message.

[0174] Note that the report timing setting information may include the s-measure suitable for the drone 200 separately from the s-measure suitable for the terminal device 300. Alternatively, the report timing setting information may include an offset value indicating the difference between the s-measure suitable for the terminal device 300 and the s-measure suitable for the drone 200.

[0175] In addition, the reporting timing setting information may include a scaling factor for scaling s-measure.

[0176] For example, the report timing setting information may include information indicating a report condition regarding the altitude information. Specifically, the report timing setting information may include a threshold value corresponding to the altitude information. In the case where the report timing setting information includes a threshold value corresponding to the altitude information, the drone 200 sends a measurement report message at a timing when the altitude indicated by the altitude information exceeds or falls below the threshold value. In this way, the drone 200 can send a measurement report message according to the altitude information.

[0177] For example, the report timing setting information may include information indicating a waiting time (e.g., time-to-trigger (TTT)) from when the report condition is satisfied to when the measurement report message is sent. In the case where the report timing setting information includes information indicating the waiting time, after the waiting time has passed since the report condition is satisfied, the drone 200 sends the measurement report message. Note that the report timing setting information may include a scaling factor for scaling the waiting time.

[0178] Note that the report timing setting information may include the parameter itself to be set, or may include the amount of change from the current setting.

[0179] (5) Speed ​​reference

[0180] The drone 200 (e.g., the measurement report control unit 253) may further control the measurement report processing based on the speed information indicating the speed of the drone 200. The speed information to be referenced for controlling the measurement report processing may be information indicating the speed in the vertical direction, such as the climbing speed and the descending speed. In this case, the drone 200 may recognize or predict in advance the transition of the altitude region with higher accuracy and reflect the transition in the measurement report processing, so that the drone 200 may perform appropriate handover associated with the reflection. In addition, the speed information to be referenced for controlling the measurement report processing may be information indicating the speed in the three-dimensional direction as well as the vertical direction. In this case, the drone 200 may predict or recognize in advance the positional relationship with the cell range in the three-dimensional direction and reflect the positional relationship in the measurement report processing, so that the drone 200 may perform appropriate handover associated with the reflection.

[0181] To this end, first, the drone 200 (e.g., the acquisition unit 251) acquires speed information indicating a measurement result of the speed. For example, the speed information may be measured by the sensor unit 243. That is, the drone 200 may acquire the speed information from the flight device 240. There are various methods for measuring the speed information. For example, the speed information may be calculated based on the acceleration measured by the acceleration sensor. In addition, the speed information may be calculated based on a time change of the altitude indicated by the altitude information.

[0182] By combining two or more of these measurement methods, the drone 200 can further improve the accuracy of the speed information. In addition, by correcting the measured speed information using the correction data transmitted from the base station 100, the drone 200 can further improve the accuracy of the speed information.

[0183] In addition, the speed information may be measured by other devices. For example, the speed information may be measured by another drone 200 flying near the drone 200. In addition, the speed information may be calculated by the base station 100 based on the time change of the altitude indicated by the altitude information. In these cases, the drone 200 receives the speed information from the other devices.

[0184] In a manner similar to the control based on the altitude information, the control of the measurement report processing based on the speed information includes the control of the measurement timing and the control of the report timing.

[0185] -Measurement timing

[0186] The drone 200 (e.g., the measurement report control unit 253) can measure the altitude at a timing based on a parameter corresponding to the speed information. In this way, the drone 200 can, for example, increase the frequency of altitude measurement as the speed increases, thereby facilitating the determination of handover of the base station 100.

[0187] In this case, the altitude measurement timing setting information notified from the base station 100 to the drone 200 includes a parameter regarding the speed information. In this way, the measurement timing of the altitude becomes a timing based on the parameter regarding the speed information. For example, the drone 200 measures the altitude at a timing when the speed indicated by the speed information exceeds or falls below a threshold. In addition, the drone 200 may control the measurement cycle according to the speed information, or may scale the measurement cycle.

[0188] -Report timing

[0189] The drone 200 (e.g., the measurement report control unit 253) may report the measurement report message to the base station 100 at a timing based on a parameter corresponding to the speed information. In this way, the drone 200 may increase the reporting frequency as the speed increases, thereby facilitating the handover judgment of the base station 100.

[0190] In this case, the report timing setting information notified from the base station 100 to the drone 200 includes a parameter regarding the speed information. In this way, the report timing becomes a timing based on the parameter regarding the speed information. For example, the drone 200 sends a measurement report message at a timing when the speed indicated by the speed information exceeds or falls below a threshold. In addition, the drone 200 may control the report cycle according to the speed information, or may scale the report cycle.

[0191] Of course, the measurement report process may be controlled based on a combination of the altitude information and the speed information. In addition, the measurement report message may include speed information.

[0192] (6) Terminal attribute information

[0193] The drone 200 (e.g., the measurement report control unit 253) notifies the base station 100 of information indicating that a process corresponding to the relationship between the altitude information and the altitude region setting information is performed. More simply, the drone 200 notifies the base station 100 of information indicating whether the drone 200 has flight capability, that is, information indicating whether the drone 200 is a drone. In the following description, this information will also be referred to as terminal attribute information (corresponding to UE capability information in LTE).

[0194] The base station 100 can recognize that the drone 200 is a drone from the terminal attribute information, and notify the information for the drone (such as altitude area setting information, altitude measurement timing setting information, and report timing setting information). Note that the base station 100 can notify the drone 200 of an inquiry message for requesting the drone 200 to notify the terminal attribute information.

[0195] (7) Measurement report message

[0196] The drone 200 reports a measurement report message to the base station 100. The measurement report message includes at least one of reference signal information or altitude information. Generally, the measurement report message includes both reference signal information and altitude information. In addition, the measurement report message may include speed information.

[0197] The measurement report message includes a measurement result IE corresponding to the measurement ID of the report object. Note that the measurement ID is identification information associated with a reference signal measurement process or a height measurement process.

[0198] There is a case where the period of the height measurement timing is different from the period of the report timing. Therefore, for example, the measurement report message may include multiple copies of height information or an average value of the multiple copies of height information. In addition, the number of copies of height information to be reported may be limited to a predetermined number immediately before the report, or a predetermined number of copies of height information or an average value of a predetermined number of copies of height information may be reported.

[0199] (8) Handover

[0200] The base station 100 (e.g., the handover control unit 155) controls a handover process corresponding to the measurement report message reported from the drone 200. For example, the base station 100 determines whether the handover can be performed and selects a target base station based on at least one of the altitude information, speed information, or reference signal information included in the measurement report message reported from the drone 200. In the case of performing the handover, the base station 100 sends a handover request to the target base station.

[0201] (9) Processing flow

[0202] Reference will be made later Fig.10 and Fig.11 , describing the processing flow in this embodiment.

[0203] Fig.10 2 is a flowchart illustrating an example of the flow of measurement report processing performed at the drone 200 according to the present embodiment. Fig.10 As shown in the diagram, first, the drone 200 receives the altitude area setting information from the base station 100 (step S202). Subsequently, the drone 200 sets the altitude measurement timing based on the relationship between the altitude information and the altitude area setting information (step S204). Then, the drone 200 sets the report timing based on the relationship between the altitude information and the altitude area setting information (step S206). After that, the drone 200 measures the altitude according to the set altitude measurement timing, and reports the measurement report message according to the set report timing.

[0204] Fig.111 is a sequence diagram illustrating an example of the flow of measurement report processing performed in the system 1 according to the present embodiment. The sequence involves the base station 100 and the drone 200.

[0205] like Fig.11 As shown in the diagram, when the drone 200 is camped on, the drone 200 obtains system information from the base station 100 (step S302). The system information includes, for example, altitude zone setting information.

[0206] Subsequently, the base station 100 inquires the drone 200 about the terminal attribute information (step S304), and the drone 200 transmits the terminal attribute information to the base station 100 (step S306). In this way, the base station 100 recognizes that the communication partner is a drone.

[0207] Subsequently, the base station 100 transmits an RRC connection reconfiguration message including, for example, altitude measurement timing setting information and report timing setting information to the drone 200 (step S308). More specifically, the base station 100 transmits parameters for setting altitude measurement timing and report timing corresponding to the relationship between the altitude information and the altitude region setting information to the drone 200.

[0208] Subsequently, the drone 200 measures the altitude at a timing corresponding to the altitude measurement timing setting information, that is, at a timing based on a parameter corresponding to the relationship between the altitude information and the altitude region setting information (step S310 ).

[0209] Subsequently, the drone 200 reports at a timing corresponding to the report timing setting information. For example, the drone 200 determines a reporting condition (step S312). More specifically, the drone 200 determines whether the timing to be determined (e.g., the current time) is a timing based on a parameter corresponding to the relationship between the altitude information and the altitude region setting information. Subsequently, in the case where it is determined that the reporting condition is satisfied, the drone 200 reports a measurement report message including reference signal information and altitude information to the base station 100 (step S314).

[0210] <<4. Application Examples>>

[0211] The technology disclosed in the present invention can be applied to various products. For example, the base station 100 can be implemented as any type of evolved node B (eNB), such as a macro eNB or a small eNB. A small eNB can be an eNB that covers a cell smaller than a macro cell, such as a pico eNB, a micro eNB, or a home (flying) eNB. The base station 100 can be implemented as another type of base station, such as a Node B or a base transceiver station (BTS). The base station 100 may include a main entity (also referred to as a base station device) that controls wireless communication and one or more remote radio heads (RRHs) that are placed in a place different from the main entity. In addition, the various terminals described below can act as the base station 100 by temporarily or semi-permanently performing base station functions.

[0212] <4.1. Application examples of base stations>

[0213] (First Application Example)

[0214] Fig.12 8 is a block diagram illustrating a first example of a schematic configuration of an eNB to which the technology according to the present disclosure is applicable. The eNB 800 includes one or more antennas 810 and a base station device 820. Each antenna 810 and base station device 820 may be connected to each other via an RF cable.

[0215] Each antenna 810 includes a single or multiple antenna elements (e.g., multiple antenna elements constituting a MIMO antenna) and is used by the base station device 820 to send and receive wireless signals. The eNB 800 may include multiple antennas 810, such as Fig.12 As shown in the diagram, and for example, the multiple antennas 810 may correspond to multiple frequency bands used by the eNB 800. It should be noted that although Fig.12 The illustration illustrates an example in which the eNB 800 includes multiple antennas 810 ; however, the eNB 800 may include a single antenna 810 .

[0216] The base station device 820 includes a controller 821 , a memory 822 , a network interface 823 , and a wireless communication interface 825 .

[0217] The controller 821 may be, for example, a CPU or a DSP, and operates various functions of the upper layer of the base station device 820. For example, the controller 821 generates data packets according to the data in the signal processed by the wireless communication interface 825, and transmits the generated packets through the network interface 823. The controller 821 may generate packetized packets by packetizing data from a plurality of baseband processors to transmit the generated packetized packets. In addition, the controller 821 may also have a logical function of performing controls such as radio resource control, radio bearer control, mobility management, admission control, and scheduling. In addition, the control may be performed in coordination with surrounding eNBs or core network nodes. The memory 822 includes a RAM and a ROM, and stores programs executed by the controller 821 and various control data (such as a terminal list, transmission power data, and scheduling data).

[0218] The network interface 823 is a communication interface connecting the base station device 820 and the core network 824. The controller 821 can communicate with the core network node or another eNB through the network interface 823. In this case, the eNB 800 can be connected to the core network node or another eNB through a logical interface (e.g., an S1 interface or an X2 interface). The network interface 823 can be a wired communication interface, or a wireless communication interface for wireless backhaul. In the case where the network interface 823 is a wireless communication interface, the network interface 823 can use a higher frequency band than the frequency band used by the wireless communication interface 825 for wireless communication.

[0219] The wireless communication interface 825 supports cellular communication systems such as Long Term Evolution (LTE) or LTE-Advanced, and provides wireless connection with a terminal located in a cell of the eNB 800 through the antenna 810. The wireless communication interface 825 may generally include a baseband (BB) processor 826, an RF circuit 827, etc. The BB processor 826 may perform, for example, encoding / decoding, modulation / demodulation, multiplexing / demultiplexing, etc., and perform various signal processing on each layer (e.g., L1, media access control (MAC), radio link control (RLC), and packet data convergence protocol (PDCP)). The BB processor 826 may replace the controller 821 with part or all of the above-mentioned logical functions. The BB processor 826 may be a module including a memory storing a communication control program, a processor executing the program, and related circuits, and the function of the BB processor 826 may be changed by updating the program. In addition, the module may be a card or a blade inserted into a slot of the base station device 820, or a chip mounted on the card or blade. Meanwhile, the RF circuit 827 may include a mixer, a filter, an amplifier, etc., and transmit and receive wireless signals through the antenna 810 .

[0220] The wireless communication interface 825 may include multiple BB processors 826, such as Fig.12 As shown in the diagram, and for example, the multiple BB processors 826 may correspond to multiple frequency bands used by the eNB 800. In addition, the wireless communication interface 825 may also include multiple RF circuits 827, such as Fig.12 As shown in the diagram, and for example, the multiple RF circuits 827 may correspond to multiple antenna elements. Note that Fig.12 The illustration illustrates an example in which the wireless communication interface 825 includes a plurality of BB processors 826 and a plurality of RF circuits 827 , however, the wireless communication interface 825 may include a single BB processor 826 or a single RF circuit 827 .

[0221] exist Fig.12 In the eNB 800 shown in the diagram, the Figure 8 One or more constituent elements (e.g., the reference signal transmission unit 151, the notification unit 153, and / or the handover control unit 155) in the processing unit 150 described above may be implemented in the wireless communication interface 825. Alternatively, at least some of these constituent elements may be implemented in the controller 821. For example, a module including part (e.g., the BB processor 826) or all of the wireless communication interface 825 and / or the controller 821 may be implemented on the eNB 800. The one or more constituent elements may be implemented in the module. In this case, the module may store a program that causes the processor to function as the one or more constituent elements (in other words, a program that causes the processor to perform the operations of the one or more constituent elements) and execute the program. For another example, in the eNB 800, a program that causes the processor to function as the one or more constituent elements may be installed, and the wireless communication interface 825 (e.g., the BB processor 826) and / or the controller 821 may execute the program. In this way, the eNB 800, the base station device 820, or the module may be provided as a device including the one or more constituent elements, and a program that causes the processor to function as the one or more constituent elements may be provided. In addition, a readable recording medium recording the program can be provided.

[0222] In addition, Fig.12 In the eNB 800 shown in the diagram, reference Figure 8 The illustrated wireless communication unit 120 may be implemented in the wireless communication interface 825 (e.g., the RF circuit 827). In addition, the antenna unit 110 may be implemented at the antenna 810. In addition, the network communication unit 130 may be implemented at the controller 821 and / or the network interface 823. In addition, the storage unit 140 may be implemented at the memory 822.

[0223] (Second application example)

[0224] Fig.138 is a block diagram illustrating a second example of a schematic configuration of an eNB to which the technology of the present disclosure is applicable. The eNB 830 includes one or more antennas 840, a base station device 850, and an RRH 860. Each antenna 840 and the RRH 860 may be connected to each other via an RF cable. In addition, the base station device 850 and the RRH 860 may be connected to each other via a high-speed line such as an optical cable.

[0225] Each antenna 840 includes a single or multiple antenna elements (e.g., antenna elements constituting a MIMO antenna) and is used by the RRH 860 to transmit and receive wireless signals. The eNB 830 may include multiple antennas 840, such as Fig.13 As shown in the diagram, and for example, the plurality of antennas 840 may correspond to a plurality of frequency bands used by the eNB 830. Fig.13 The illustration illustrates an example in which the eNB 830 includes multiple antennas 840 , however, the eNB 830 may include a single antenna 840 .

[0226] The base station device 850 includes a controller 851, a memory 852, a network interface 853, a wireless communication interface 855, and a connection interface 857. The controller 851, the memory 852, and the network interface 853 are similar to those of the reference Fig.12 The controller 821, memory 822 and network interface 823 are illustrated.

[0227] The wireless communication interface 855 supports cellular communication systems such as LTE and LTE-Advanced, and provides wireless connection with a terminal located in a sector corresponding to the RRH 860 through the RRH 860 and the antenna 840. The wireless communication interface 855 may generally include a BB processor 856, etc. The BB processor 856 is similar to the reference 8 except that the BB processor 856 is connected to the RF circuit 864 of the RRH 860 via the connection interface 857. Fig.12 The wireless communication interface 855 may include multiple BB processors 856, such as Fig.13 As shown in the diagram, and for example, the plurality of BB processors 856 may correspond to a plurality of frequency bands used by the eNB 830. Fig.13 The illustration illustrates an example in which the wireless communication interface 855 includes a plurality of BB processors 856 ; however, the wireless communication interface 855 may include a single BB processor 856 .

[0228] The connection interface 857 is an interface for connecting the base station device 850 (wireless communication interface 855) and the RRH 860. The connection interface 857 may be a communication module for connecting the base station device 850 (wireless communication interface 855) and the RRH 860 for communication on a high-speed line.

[0229] In addition, the RRH 860 includes a connection interface 861 and a wireless communication interface 863 .

[0230] The connection interface 861 is an interface that connects the RRH 860 (wireless communication interface 863) and the base station device 850. The connection interface 861 may be a communication module for communication on a high-speed line.

[0231] The wireless communication interface 863 sends and receives wireless signals through the antenna 840. The wireless communication interface 863 generally includes an RF circuit 864, etc. The RF circuit 864 may include a mixer, a filter, an amplifier, etc., and sends and receives wireless signals through the antenna 840. The wireless communication interface 863 may include multiple RF circuits 864, such as Fig.13 As shown in the diagram, and for example, the plurality of RF circuits 864 may correspond to a plurality of antenna elements. Fig.13 The illustration illustrates an example in which the wireless communication interface 863 includes a plurality of RF circuits 864 ; however, the wireless communication interface 863 may include a single RF circuit 864 .

[0232] exist Fig.13 In the eNB 830 shown in the diagram, the reference Figure 8 One or more constituent elements (e.g., reference signal transmission unit 151, notification unit 153, and / or handover control unit 155) in the processing unit 150 described above may be implemented in the wireless communication interface 855 and / or the wireless communication interface 863. Alternatively, at least some of these constituent elements may be implemented in the controller 851. For example, a module including part (e.g., BB processor 856) or all of the wireless communication interface 855 and / or the controller 851 may be implemented on the eNB 830. The one or more constituent elements may be implemented in the module. In this case, the module may store a program that enables the processor to function as the one or more constituent elements (in other words, a program that enables the processor to perform the operation of the one or more constituent elements) and execute the program. For another example, in the eNB 830, a program that enables the processor to function as the one or more constituent elements may be installed, and the wireless communication interface 855 (e.g., BB processor 856) and / or the controller 851 may execute the program. In this way, the eNB 830, the base station device 850 or the module may be provided as a device including the one or more constituent elements, and a program for causing a processor to function as the one or more constituent elements may be provided. In addition, a readable recording medium recording the program may be provided.

[0233] In addition, Fig.13 In the eNB 830 shown in the diagram, for example, reference Figure 8The illustrated wireless communication unit 120 may be implemented in the wireless communication interface 863 (e.g., the RF circuit 864). In addition, the antenna unit 110 may be implemented at the antenna 840. In addition, the network communication unit 130 may be implemented at the controller 851 and / or the network interface 853. In addition, the storage unit 140 may be implemented at the memory 852.

[0234] <<5. Conclusion>>

[0235] Reference above Figures 1 to 13 , an embodiment of the present disclosure has been described in detail. As described above, the drone 200 according to the present embodiment obtains altitude information indicating the measurement result of the altitude, and based on the relationship between the altitude information and the altitude area setting information, controls the measurement report processing of reporting to the base station 100 the reference signal information indicating the measurement result of the reference signal sent from the base station 100 and the measurement report message of the altitude information. In this way, the base station 100 can grasp the altitude of the drone 200 and enable the drone 200 to appropriately perform handover. In association with this, since the failure of handover of the drone 200 is reduced, the handover becomes efficient. As a result, the operator can achieve the accommodation of many drones 200 using small cells.

[0236] The preferred embodiments of the present disclosure have been described above with reference to the accompanying drawings, but the present disclosure is not limited to the above examples. Within the scope of the attached claims, various modifications and variations can be obtained by those skilled in the art, and it should be understood that the various modifications and variations are naturally within the technical scope of the present disclosure.

[0237] For example, although it is described that the altitude area setting information, the altitude measurement timing setting information, and the report timing setting information are notified from the base station 100 to the drone 200, the source of providing the information is not limited to the base station 100. For example, the information may be provided from a server on the Internet and notified to the drone 200 through the base station 100.

[0238] In addition, the drone 200 is not limited to a drone in a narrow sense. For example, the drone 200 can be any aircraft controlled through cellular communication.

[0239] Furthermore, although the above description is mainly about the high-speed flight altitude region, the present technology is not limited to such an example. For example, the present technology can be applied to other altitude regions such as the low-speed flight altitude region.

[0240] In addition, in this specification, the processing described by using flowcharts and sequence diagrams does not necessarily have to be performed in the order shown in the diagrams. Some processing steps can be performed in parallel. In addition, other processing steps can be adopted, or some processing steps can be omitted.

[0241] In addition, the effects described in this specification are merely illustrative or exemplary, and not restrictive. That is, together with or in place of the above effects, other effects that are clear to those skilled in the art based on the description of this specification can be obtained according to the technology disclosed in this disclosure.

[0242] Additionally, the present technology may also be configured as follows.

[0243] (1) A circuit comprising:

[0244] an acquisition unit configured to acquire altitude information indicating a measurement result of an altitude; and

[0245] A measurement report control unit, wherein the measurement report control unit is configured to control the measurement report processing of reporting to the base station reference signal information indicating the measurement result of the reference signal sent from the base station and the measurement report message of the height information based on the relationship between the height information acquired by the acquisition unit and the height area setting information.

[0246] (2) A circuit according to (1),

[0247] In the case where the altitude area set by the altitude area setting information includes the altitude indicated by the altitude information, or where the difference between the upper limit or lower limit of the altitude area set by the altitude area setting information and the altitude indicated by the altitude information is within a threshold, the measurement report control unit uses parameters corresponding to the altitude area to control the measurement report processing.

[0248] (3) A circuit according to (1) or (2),

[0249] The measurement report control unit causes the altitude to be measured at a timing based on a parameter corresponding to the relationship.

[0250] (4) A circuit according to any one of (1) to (3),

[0251] The measurement report control unit reports the measurement report message to the base station at a timing based on a parameter corresponding to the relationship.

[0252] (5) A circuit according to any one of (1) to (4),

[0253] wherein the acquisition unit acquires speed information, and

[0254] The measurement report control unit further controls the measurement report process based on the speed information.

[0255] (6) The circuit according to (5),

[0256] The measurement report control unit causes the altitude to be measured at a timing based on a parameter corresponding to the speed information.

[0257] (7) The circuit according to (5) or (6),

[0258] The measurement report control unit reports the measurement report message to the base station at a timing based on a parameter corresponding to the speed information.

[0259] (8) A circuit according to any one of (5) to (7),

[0260] The speed information is information indicating the speed in the vertical direction.

[0261] (9) A circuit according to any one of (1) to (8),

[0262] The measurement report control unit notifies the base station of information instructing to perform a process corresponding to the relationship.

[0263] (10) A circuit according to any one of (1) to (9),

[0264] The measurement report control unit determines the relationship while providing a hysteresis.

[0265] (11) The circuit according to any one of (1) to (10),

[0266] The altitude zone setting information at least includes settings regarding an altitude zone in which high-speed flight can be performed.

[0267] (12) The circuit according to any one of (1) to (11),

[0268] The acquisition unit acquires the altitude information from a flying device capable of flying.

[0269] (13) The circuit according to (12),

[0270] Wherein the circuit is connected to the flight device.

[0271] (14) A base station, comprising:

[0272] a reference signal transmitting unit configured to transmit a reference signal; and

[0273] A notification unit, wherein the notification unit is configured to notify the terminal device of the altitude zone setting information, and the terminal device controls the measurement report processing of the measurement report message including the reference signal information indicating the measurement result of the reference signal and the altitude information based on the relationship between the altitude information indicating the measurement result of the altitude and the altitude zone setting information.

[0274] (15) The base station according to (14),

[0275] The notification unit includes the altitude zone setting information in system information or a radio resource control (RRC) connection reconfiguration message and notifies the information.

[0276] (16) The base station according to (14) or (15), further comprising:

[0277] A handover control unit configured to control a handover process corresponding to a measurement report message reported from the terminal device.

[0278] (17) A method comprising:

[0279] obtaining altitude information indicating the measurement of altitude; and

[0280] The processor controls measurement report processing of reporting to the base station reference signal information indicating a measurement result of a reference signal sent from the base station and a measurement report message of the altitude information based on the relationship between the acquired altitude information and the altitude region setting information.

[0281] (18) A method comprising:

[0282] sending a reference signal; and

[0283] The height zone setting information is notified to the terminal device through the processor, and the terminal device controls the measurement report processing of the measurement report message including the reference signal information indicating the measurement result of the reference signal and the height information based on the relationship between the height information of the measurement result indicating the height and the height zone setting information.

[0284] (19) A recording medium having a program recorded thereon, the program causing a computer to:

[0285] an acquisition unit configured to acquire altitude information indicating a measurement result of an altitude; and

[0286] A measurement report control unit, wherein the measurement report control unit is configured to control the measurement report processing of reporting to the base station reference signal information indicating the measurement result of the reference signal sent from the base station and the measurement report message of the height information based on the relationship between the height information acquired by the acquisition unit and the height area setting information.

[0287] (20) A recording medium having a program recorded thereon, the program causing a computer to:

[0288] a reference signal transmitting unit configured to transmit a reference signal; and

[0289] A notification unit, wherein the notification unit is configured to notify the terminal device of the altitude zone setting information, and the terminal device controls the measurement report processing of the measurement report message including the reference signal information indicating the measurement result of the reference signal and the altitude information based on the relationship between the altitude information indicating the measurement result of the altitude and the altitude zone setting information.

[0290] Reference numerals list

[0291] 1 System

[0292] 31 High-speed flight altitude area

[0293] 100 Base Stations

[0294] 110 antenna units

[0295] 120 Wireless Communication Unit

[0296] 130 Network Communication Unit

[0297] 140 storage units

[0298] 150 Processing Units

[0299] 151 Reference signal sending unit

[0300] 153 Notification Unit

[0301] 155 Handover control unit

[0302] 200 Terminal equipment, drone

[0303] 210 antenna units

[0304] 220 Wireless Communication Unit

[0305] 230 storage units

[0306] 240 Flight Equipment

[0307] 241 Drive Unit

[0308] 242 battery cells

[0309] 243 Sensor unit

[0310] 244 Flight Control Unit

[0311] 250 processing units

[0312] 251 Get Unit

[0313] 253 Measurement report control unit

[0314] 300 terminal equipment

Claims

1. An aircraft, comprising: A processing circuit, the processing circuit being configured to: receiving a reference signal from a base station, acquiring altitude information indicating a measurement result of an altitude and altitude region setting information, wherein the altitude region setting information is information for setting an altitude region for classifying a state of an altitude region of the aircraft, identifying the altitude zone of the aircraft based on the altitude information and the altitude zone setting information, sending a measurement report message, the measurement report message including measurement information indicating a measurement result of the reference signal sent from a base station and the altitude information indicating a measurement result of an altitude of the aircraft, and A measurement report process of reporting the measurement report message is controlled based on the identified altitude zone of the aircraft, so that a frequency of sending the measurement report message is changed according to the identified altitude zone of the aircraft.

2. The aircraft according to claim 1, wherein: The processing circuit is further configured to control the measurement report process of reporting the measurement report message based on a relationship between the altitude information and the altitude region setting information.

3. The aircraft according to claim 1, wherein: The altitude area setting information is included in system information or a radio resource control (RRC) connection reconfiguration message.

4. The aircraft according to claim 1, wherein: The processing circuit is further configured to change the frequency of sending the measurement report message such that the frequency is higher as the identified altitude region of the aircraft becomes higher. The aircraft according to claim 1 , wherein the aircraft is an unmanned aerial vehicle.

6. A base station, comprising: A processing circuit, the processing circuit being configured to: Send a reference signal to the terminal device, sending altitude information indicating the measurement result of the altitude and altitude region setting information to the terminal device, wherein the altitude region setting information is information for setting an altitude region for classifying the state of the altitude region of the aircraft, and receiving a measurement report message from the terminal device, the measurement report message including measurement information indicating a result of measurement of the reference signal by the terminal device and the altitude information indicating a measurement result of the altitude of the aircraft, wherein: The terminal device identifies the altitude zone of the aircraft based on the altitude information and the altitude zone setting information, The terminal device controls the measurement report process of reporting the measurement report message based on the identified altitude zone of the aircraft, so that the frequency of sending the measurement report message is changed according to the identified altitude zone of the aircraft, and The processing circuit is further configured to control reception of the measurement report message sent with the frequency.

7. The base station according to claim 6, wherein: The altitude area setting information is included in system information or a radio resource control (RRC) connection reconfiguration message.

8. The base station according to claim 6, wherein: The processing circuit is further configured to control a handover process corresponding to the measurement report message reported from the terminal device.

9. The base station according to claim 6, wherein: The terminal device is arranged in the aircraft.

10. The base station according to claim 6, wherein: The aircraft is an unmanned aerial vehicle.

11. A method for an aircraft, comprising: receiving a reference signal from a base station, acquiring altitude information indicating a measurement result of an altitude and altitude region setting information, wherein the altitude region setting information is information for setting an altitude region for classifying a state of an altitude region of the aircraft, identifying the altitude zone of the aircraft based on the altitude information and the altitude zone setting information, sending a measurement report message, the measurement report message including measurement information indicating a measurement result of the reference signal sent from a base station and the altitude information indicating a measurement result of an altitude of the aircraft, and A measurement report process of reporting the measurement report message is controlled based on the identified altitude zone of the aircraft, so that a frequency of sending the measurement report message is changed according to the identified altitude zone of the aircraft.

12. A method for a base station, comprising: Send a reference signal to the terminal device, sending altitude information indicating the measurement result of the altitude and altitude region setting information to the terminal device, wherein the altitude region setting information is information for setting an altitude region for classifying the state of the altitude region of the aircraft, and receiving a measurement report message from the terminal device, the measurement report message including measurement information indicating a result of measurement of the reference signal by the terminal device and the altitude information indicating a measurement result of the altitude of the aircraft, wherein: The terminal device identifies the altitude zone of the aircraft based on the altitude information and the altitude zone setting information, The terminal device controls the measurement report process of reporting the measurement report message based on the identified altitude zone of the aircraft, so that the frequency of sending the measurement report message is changed according to the identified altitude zone of the aircraft, and The method also includes controlling reception of the measurement report message sent using the frequency.

13. A recording medium having a program recorded thereon, the program causing a computer to execute a method for an aircraft, the method comprising: receiving a reference signal from a base station, acquiring altitude information indicating a measurement result of an altitude and altitude region setting information, wherein the altitude region setting information is information for setting an altitude region for classifying a state of an altitude region of the aircraft, identifying the altitude zone of the aircraft based on the altitude information and the altitude zone setting information, sending a measurement report message, the measurement report message including measurement information indicating a measurement result of the reference signal sent from a base station and the altitude information indicating a measurement result of an altitude of the aircraft, and A measurement report process of reporting the measurement report message is controlled based on the identified altitude zone of the aircraft, so that a frequency of sending the measurement report message is changed according to the identified altitude zone of the aircraft.

14. A recording medium having a program recorded thereon, the program causing a computer to execute a method for a base station, the method comprising: Send a reference signal to the terminal device, sending altitude information indicating the measurement result of the altitude and altitude region setting information to the terminal device, wherein the altitude region setting information is information for setting an altitude region for classifying the state of the altitude region of the aircraft, and receiving a measurement report message from the terminal device, the measurement report message including measurement information indicating a result of measurement of the reference signal by the terminal device and the altitude information indicating a measurement result of the altitude of the aircraft, wherein: The terminal device identifies the altitude zone of the aircraft based on the altitude information and the altitude zone setting information, The terminal device controls the measurement report process of reporting the measurement report message based on the identified altitude zone of the aircraft, so that the frequency of sending the measurement report message is changed according to the identified altitude zone of the aircraft, and The method also includes controlling reception of the measurement report message sent using the frequency.

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